When considering the operational performance of stainless steel weldments the most important points to consider are corrosion resistance, weld metal mechanical properties and the integrity ofthe weldedjoint. Mechanical and corrosion resistance properties are greatly influenced by the metallurgical processes that occur during welding or during heat treatment of welded components. This book is aimed, there fore, at providing information on the metallurgical problems that may be encountered during stainless steel welding. In this way we aim to help overcome a certain degree of insecurity that is often encountered in welding shops engaged in the welding of stainless steels and is often the cause of welding problems which may in some instances lead to the premature failure of the welded component. The metallurgical processes that occur during the welding of stainless steel are of a highly intricate nature. The present book focuses in particular on the signif icance of constitution diagrams, on the processes occurring during the solidification of weld metal and on the recrystallization and precipitation phenomena which take place in the area of the welds. There are specific chapters covering the hot cracking resistance during welding and the practical welding of a number of different stainless steel grades. In addition, recommendations are given as to the most suitable procedures to be followed in order to obtain maximum corrosion resistance and mechanical properties from the weldments.

Klappentext

When welding stainless steels, metallurgical reactions take place which greatly influence corrosion resistance and mechanical properties. The book deals with this subject by discussing constitution diagrams, solidification and segregation phenomenas, phase transformations, precipitations of carbides and intermetallic phases, and cracking problems. In addition, directions for welding techniques are given to avoid failures in practical welding operations.

Inhalt
1 Significance of Constitution Diagrams for the Understanding of Welding Phenomena.- 1.1 Iron-Chromium, Iron-Nickel and Chromium-Nickel Constitution Diagrams.- 1.2 The Ternary Iron-Chromium-Nickel Constitution Diagram.- 1.3 Influence of Other Elements on the Iron-Chromium-Nickel Constitution Diagram.- 2 Metallurgical Processes Occurring During Solidification and Cooling in Stainless Steel Weld Metal.- 2.1 Primary Crystallization of Weld Pools.- 2.2 Primary Crystallization of Binary and Ternary Systems.- 2.3 Phenomena at the Liquid-Solid Interface (Solidification Front).- 2.4 Crystal Growth During Solidification and Crystal Configurations.- 2.5 Primary Crystallization of Stainless Steel Weld Metals.- 2.6 Cooling Rate and Thermal Supercooling During Solidification of Stainless Steel Weld Metal.- 2.7 Segregations in Stainless Steel Weld Metal During Solidification.- 3 Metallurgical Phenomena in Secondary Crystallization of Stainless Steels and Weld Metals.- 3.1 Recrystallization of Weld Metal.- 3.2 ?-? Transformation of Stainless Steel Weld Metal.- 3.3 Schaeffler Diagram, Ferrite Measurement, DeLong Diagram.- 3.4 ?-? Transformation of Stainless Steel Alloys.- 4 Precipitation Phenomena in Stainless Steels and Weld Metals.- 4.1 Carbide Precipitations in Stainless Steels with Special Consideration to Intergranular Corrosion.- 4.2 The Precipitation of Intermetallic Phases in Stainless Steels and Weld Metals.- 4.3 475° C Embrittlement in Stainless Steels and Stainless Steel Weld Metals.- 5 Hot Cracking Resistance During the Welding of Austenitic Stainless Steels.- 5.1 Formation of Hot Cracks.- 5.2 Hot Cracking Tests.- 5.3 Criteria which Influence the Hot Cracking Susceptibility of Austenitic Stainless Steel Weldments.- 6 Welding Metallurgy of Ferritic Stainless ChromiumSteels with Carbon Contents Below 0.15%.- 6.1 Practical Welding of Stainless Chromium Steels.- 6.2 Mechanical Properties of Stainless Steel Weld Metals with 12 and 17% Chromium.- 6.3 Precipitation Phenomena in Ferritic Stainless Chromium Steels and Weld Metals.- 7 Welding Metallurgy of Low Carbon Chromium-Nickel Martensitic Stainless Steels (Soft Martensitic Steels).- 7.1 Practical Welding of Low Carbon Martensitic Stainless Steels.- 7.2 Mechanical Properties of Low Carbon Martensitic Stainless Steel Weld Metal.- 7.3 Precipitation Phenomena in Low Carbon Soft Martensitic Stainless Steels and Weld Metals.- 8 Welding Metallurgy of Duplex Austenitic-Ferritic Stainless Steels.- 8.1 Practical Welding of Duplex Austenitic-Ferritic Stainless Steels.- 8.2 Mechanical Properties of Duplex Austenitic-Ferritic Stainless Steel Weld Metal.- 8.3 Precipitation Phenomena in Duplex Austenitic-Ferritic Stainless Steels and Weld Metals.- 9 Welding Metallurgy of Austenitic Stainless Steels.- 9.1 Welding Metallurgy of Unstabilized Austenitic Stainless Steels.- 9.2 Welding Metallurgy of Stabilized Austenitic Stainless Steels.- 9.3 Welding Metallurgy of Fully Austenitic Stainless Steels.- 10 General Instructions for the Welding and Post-Weld Surface Treatments of Fabrications and Welded Components Made from Austenitic Stainless Steel.- 10.1 Welding Procedure.- 10.2 Welding of Austenitic Stainless Steel Castings.- 10.3 Post Weld Surface Treatments.- 11 Welding Metallurgy of Heat Resisting Steels.- 12 Welding Metallurgy of Austenitic-Ferritic Dissimilar Joints.- 12.1 Selection of Filler Metals and Importance of Dilution.- 12.2 Practical Welding of Austenitic-Ferritic Dissimilar Joints.- 12.3 Criteria for the Heat Treatment of Austenitic-Ferritic Dissimilar Joints.- 12.4 Mechanical Properties ofAustenitic-Ferritic Dissimilar Joints.- Appendix (Abbreviations and Short Designations).- References.- Author Index.